The present invention relates to detergent compositions containing as an essential component a plurality of rinse cycle suds control prills. More specifically, the invention in its broadest context encompasses detergent compositions comprising a surfactant, a detergency builder, and a plurality of rinse cycle suds control prills.
Soiled clothing is frequently laundered by being placed in a mechanical washing machine along with the prescribed quantity of a detergent composition and water. The soiled clothing is then agitated in the aqueous solution of the detergent composition for the requisite period of time in what is called the "wash cycle." At the end of the wash cycle, most of the aqueous solution of the detergent composition, along with suspended soils, is drained from the washing machine and otherwise mechanically removed from the clothing. Additional fresh water is introduced into the washing machine in an effort to remove residual soil and detergent composition in one or more "rinse cycles." Currrently available detergent compositions can provide adequate, and even exemplary, soil removal from the clothing during the wash cycle. Depending upon the type of washing machine involved and the particular detergent composition, a level of suds is maintained on the surface of the wash water during the wash cycle. This level of suds, among other things, serves to indicate to the person responsible for laundering the clothes that the requisite amount of detergent composition has been used in the wash cycle. After the aqueous solution of the detergent composition has been removed from the clothing at the end of the wash cycle, a finite quantity of the surfactant remains with the clothing and is carried forward into the rinse cycle. This surfactant from the detergent composition frequently causes a layer of suds to be produced on the surface of the water in the washing machine during the rinse cycle. Unlike the layer of suds on the surface of the water during the wash cycle, many people consider the layer of suds on the surface of the water during the rinse cycle to be aestheticly displeasing.
Silicones have been used and taught as effective agents for controlling suds during a wash cycle. For example, U.S. Pat. No. 3,455,839 issued to Lawrence A. Rauner, on July 15, 1969 relates to compositions and processes for defoaming aqueous solutions by incorporating therein small amounts of polydimethylsiloxane fluids.
U.S. Pat. No. 4,136,045 issued to Gault and Maguire, Jr. on Jan. 23, 1979 discloses the combination of nonionic surfactant and a silicone suds suppressing agent in detergent compositions to reduce suds during the wash cycle.
U.S. Pat. No. 3,829,386 issued Wegst et al on Aug. 13, 1974 also discusses a combination of nonionic surfactant and silicone fluid added to a detergent composition to provide suds control during the wash cycle.
It is an object of the present invention to provide a granular detergent composition which exhibits control of suds during the rinse cycle, while enabling aesthetically pleasing levels of suds to be maintained in the wash cycle.